Core dump report

[Lendvai Attila]

I've forgotten the code that triggers it:

fileName1@(File Locator traits) compareContentsTo: fileName2@(File
Locator traits)
[
  (File newNamed: fileName1 &mode: File Read) sessionDo:
    ([| :file1 |
      (File newNamed: fileName2 &mode: File Read) sessionDo:
        [| :file2 |
	   t copmareFileContents: file1 with: file2
        ]
    ] on: Stream Exhaustion do: [| :c | ^ False]).
].


take a look at the () around a [] with an ensure: call. I assumed that
([] ensure: [| :c | ]) returns a block with an ensure attached and used
it for sessionDo: ... after looking at the interpreter code it may be
illegal.

so what is the official answer, is it a bug / an illegal code / not yet
supported feature?

- 101

:: hi!
:: 
:: in prims.slate:
:: 
:: body at CompiledMethodTraits ensure: unwindBlock at CompiledMethodTraits [
::   interpreter
::     apply: body pointer!(CompiledMethod pointer) cast
::     to: Nil
::     arity: 0
::     withOptionals: Nil.
::   interpreter lexicalContext unwindBlock: unwindBlock
:: ] `pidginPrimitive. 
:: 
:: 
:: in vm.slate:
:: 
:: i@(Interpreter pointer) apply: method to: args arity: n 
:: withOptionals: opts [| method!(CompiledMethod pointer) 
:: args!(ObjectPointer pointer) opts!(OopArray pointer) 
:: lexicalContext!(LexicalContext pointer) inputs |
::    lexicalContext: (CurrentMemory newOopArray: LexicalContextProto
:: sized: method localVariables asSmallInt)!(LexicalContext 
:: pointer) cast.
::    inputs: method inputVariables asSmallInt.
::    args!(Word pointer) cast
::      copyWords: inputs
::      into: lexicalContext variables!(Word pointer) cast.
:: ...
:: 
:: So the upper one calls the lower one, with to: Nil (probably 
:: instead of ObjectHeap NilObject) and it causes the apply 
:: method to access 0x00000000 as the value of Nil is 0.
:: 
:: I don't know exactly what's happening there, so I leave it 
:: for Lee... :) Could be that apply and friends should be 
:: prepared for Nil...
:: 
:: Make sure to look around in there (prims.slate), because 
:: there are quite a few Nil's used all around. Could be other 
:: problems, too. (If it is a problem at all, as opposed to me 
:: screwing up something)
:: 
:: Happy coding,
:: 
:: - 101
:: 
:: 
::